Conventionally, a Bluetooth communicator providing wireless communications according to the specifications of the Bluetooth is used widely. The specifications of the Bluetooth include different profiles, each of which defines functions necessary for a mode of the operation of the Bluetooth communicator. A handsfree profile (HFP) for providing a handsfree function and a dial-up network profile (DUN) for providing data communications through a dial-up connection on a telephone line are examples of the profiles.
FIG. 7 is a sequence chart which illustrates an exemplary procedure of communications for establishing a connection of the Bluetooth between a handsfree device and a mobile phone handset and for providing the functions of the handsfree profile and the dial-up network profile.
In the figure, the handsfree device and the handset is maintaining a connection for the handsfree profile with each other (State 505). Then, a user's operation 510 to the handsfree device for starting data communications causes the handsfree device to transmit, to the handset, an HFP disconnection request signal 515 for requesting for cutting off the connection for the handsfree profile. In response to the signal 515, the handset returns, to the handsfree device, an HFP disconnection response signal 520 including a message of “OK.” Then, the handsfree device and the handset terminate processes for the handsfree profile.
Next, the handsfree device transmits a DUN connection request signal 525 to the handset in order to establish a connection for the dial-up network profile. In response to the signal 525, the handset returns a DUN connection response signal 530 including a message of “OK” to the handsfree device. Then the wireless communications for the dial-up network profile are established and thus the handsfree device opens a connection with a wide-area network such as the Internet by using the phone calling function of the handset, and executes data communications such as Web browsing through the wide-area network (State 535).
When the data communications end due to an operation 540 of the user, the handsfree device transmits, to the handset, a DUN disconnection request signal 545 for requesting for cutting off the connection for the dial-up network profile. In response to the signal 545, the handset returns a DUN disconnection response signal 550 including a message of “OK” to the handsfree device. Then, the handsfree device and the handset terminate processes for the dial-up network profile.
Next, the handsfree device transmits an HFP connection request signal 555 to the handset in order to establish a connection for the handsfree profile. In response to the signal 555, the handset returns an HFP connection response signal 560 including a message of “OK” to the handsfree device. Then the communications for the handsfree profile is established and thus the handsfree device becomes capable of receiving and sending a phone call by using the phone calling function of the handset (State 565).
Although the handset in the above example provides both the handsfree profile function and the dial-up profile function, it does not provide both the functions at a time. In other words, the handset stops one of the handsfree profile function and the dial-up profile function while it is providing the other profile function.
However, multi-profile compatible Bluetooth communicators have become available in recent years. The multi-profile compatible Bluetooth communicator is capable of providing functions for a plurality of profiles at a time. By using the multi-profile compatibility of both the handsfree device and the mobile phone handset, both the handsfree profile function and the dial-up network profile function can be provided at a time in the connection between the handsfree device and the handset. In this case, the handset can mediate the dial-up connection of the handsfree device and transmit a notification of an incoming phone call to the handsfree device, at the same time.
However, a multi-profile compatible Bluetooth communicator does not always connect with a comparable multi-profile compatible Bluetooth communicator. There may be a case where a multi-profile compatible Bluetooth communicator starts to communicate with a certain Bluetooth communicator having no multi-profile compatibility by supposing that the certain Bluetooth communicator should have multi-profile compatibility. In this case, problems may arise in establishing a connection between the two Bluetooth communicators.